Many children have abnormalities in bone growth that lead to a variety of conditions such as scoliosis or disproportional long bone growth, such as in the legs or arms. For children suffering from scoliosis, if the curvature of the spine is severe enough, the child will require surgery to correct the curvature of the spine. The surgery typically involves the fusion of one or more vertebrae of the spine together to correct the curvature. Spinal surgery is complicated, high risk, costly, and requires a long period of convalescence.
Correcting disproportionate bone growth in an extremity is typically accomplished by performing an epiphysiodesis, which disrupts or destroys a selected growth plate for the purpose of delaying the longitudinal growth of the involved extremity. For example, a child may have a leg length discrepancy of 1 inch, which may be treated by performing an epiphysiodesis of a selected growth plate of the longer leg at a selected age. The epiphysiodesis of the selected growth plate inhibits residual longitudinal growth of the longer leg, and, as the child continues to grow, the continued growth of the shorter leg decreases the discrepancy. Timing of the current techniques is important since typically this ablation is permanent and its performance must be closely linked with the natural termination of growth.
One procedure for performing an epiphysiodesis is the Phemister technique. This technique involves making two to three inch incisions placed medially and laterally on the extremity in the area of the growth plate. The growth plate is surgically explored and destroyed at its peripheral margins. More commonly used is a percutaneous method of epiphysiodesis that was developed at the A.I. duPont Hospital for Children. The percutaneous method involves making a 5 mm incision directly over the growth plate through which a curette is introduced into the physis and is ablated. With these procedures, the patient needs postoperative protection by casting and restriction of activities for three to four months. These techniques are typically permanent and require careful timing with the natural growth of the child. If the procedure is too early, it will result in the creation of a length discrepancy for over growth of the untreated bone.
There is a need for alternative procedures for correcting abnormal bone growth in an individual and in particular, an alternative method for correcting the curvature of the spine in individuals suffering from scoliosis.